xiv CONTENTS 



PAGE 



PHYLUM PROTOZOA continued. 

 Class V. Infusoria 



1. Example of the Class Paramceciv.m caudatuin .... 



2. Classification and General Organisation ... . 91 

 Systematic Position of the Example 



Further Remarks on the Protozoa . . . . . 101 



SECTION III 



PHYLUM AND CLASS PORIFERA [PARAZOA] . 



1. Example of the Class Sycon yelatinosum . . 105 



2. Distinctive Characters and Classification ... . Ill 

 Systematic Position of the Example . 



3. General Organisation ... 114 



SECTION IV 



PHYLUM COZLENTERATA . 128 



Class I. Hydrozoa 



1. Example of the Class Obelia ... . . . 128 



2. General Structure and Classification 140 



Systematic Position of the Example .... . 142 



Additional Remarks ... 167 



Class II. Scyphozoa . . 168 



1. Example of the Class Aurelia aurita 168 



2. General Structure and Classification 176 



Systematic Position of the Example 177 



Additional Remarks 184 



Class III. Actinozoa , . 185 



1. Example of the Class Tealia crassicornis 185 



2. Distinctive Characters and Classification 193 



Systematic Position of the Example . . . 196 



3. General Organisation . 196 



Class IV. Ctenophora 211 



1. Example of the Class Hormiphora plumosa 211 



2. Distinctive Characters and Classification 220 



Systematic Position of the Example ... . 221 



3. General Organisation . 222 



Appendix to Ctenophora Ctenoplana and Codoplana . . . 225 



The Relationships of the Coelenterata 226 



Appendix to the Coelenterata The Mesozoa 230 



SECTION V 



PHYLUM PLATYHELMINTHES . 235 



1. Examples of the Phylum 236 



i. Planaria or Dendrocoeliim 236 



ii. Fasciola hepatica . 240 



iii. Tania soliuni 245 



